Brown discharge .. Late period PLEASE HELP

Brown discharge ... my period is 11 days late and I see that it could be implantation/ spotting and all but the closest thing to having sex was just messing around with my boyfriend. We didn't have sex so I doubt that I'm pregnant and I took a test & it was negative... am i just stressing? is this a sign that my period is coming. I only see this when I'm wipe so there's not enough to get on my panties